Tensor calculus

1. The problem statement, all variables and given/known data
equation of ellipse may be written ax^2 + 2hxy + by^2 =1
What is the tensor charater of a, h, b with respect to transformation to
any Cartesian coordinates(rectangle or oblique) in the plane?

2. Relevant equations
none

3. The attempt at a solution
no idea1. The problem statement, all variables and given/known data